Redmine why plugins don't work?

Question

Redmine

Comrades, there was such a problem.
Ubuntu 16.04+Redmine 3.4.4

spoiler

Environment:
  Redmine version                3.4.4.stable
  Ruby version                   2.5.1-p57 (2018-03-29) [x86_64-linux-gnu]
  Rails version                  4.2.10
  Environment                    production
  Database adapter               Mysql2
SCM:
  Git                            2.17.1
  Filesystem                     
Redmine plugins:
  redmine__select2               1.1.0
  redmine_agile                  1.4.10
  redmine_ckeditor               1.1.7
  redmine_issues_tree            0.0.10
  redmine_zenedit                1.0.2

I cover redmine with plugins. One plugin (agile) got up without problems, it functions normally. The rest of the plugins are installed without any problems, redmine sees them (in the list of plugins), but they do not work!
When choosing CKeditor as the default text editor, no toolbar is displayed, just a text field, as if no editor was specified at all.
The Zen Edit plugin is simply not in the text editor selection list.
Redmine Issues Tree plugin, plugin for issue tree structure just doesn't work: the "issue tree structure" link is there, but nothing happens when clicked.
I repeat, redmine itself sees the plugins, in the plugins menu you can rummage through their settings, but this does not lead to anything. What am I doing wrong, tell me?

Bundle complete! 31 Gemfile dependencies, 75 gems now installed.
Gems in the groups development and test were not installed.
Use `bundle info [gemname]` to see where a bundled gem is installed.
/usr/lib/ruby/vendor_ruby/sprockets/digest_utils.rb:47: warning: constant ::Fixnum is deprecated
/usr/lib/ruby/vendor_ruby/sprockets/digest_utils.rb:51: warning: constant ::Bignum is deprecated
/usr/lib/ruby/vendor_ruby/sprockets/processor_utils.rb:110: warning: constant ::Fixnum is deprecated
/usr/lib/ruby/vendor_ruby/sprockets/processor_utils.rb:111: warning: constant ::Bignum is deprecated
Migrating redmine__select2 (Redmine Select2 Plugin)...
Migrating redmine_agile (Redmine Agile plugin (Light version))...
Migrating redmine_ckeditor (Redmine CKEditor plugin)...
Migrating redmine_issues_tree (Redmine Issues Tree plugin)...
Migrating redmine_zenedit (Redmine Zen Edit plugin (Light version))...